From 2ab7f96f211bea8223bdd22ff100722d50cafa78 Mon Sep 17 00:00:00 2001 From: Chaoya Li Date: Fri, 25 Jun 2021 10:55:32 +0800 Subject: [PATCH] Backends: OpenGL3: Enable OES_vertex_array_object extension for emscripten/wasm build (#4266, #4267) --- backends/imgui_impl_opengl3.cpp | 32 +++++++++++++++++++++++++------- docs/CHANGELOG.txt | 1 + 2 files changed, 26 insertions(+), 7 deletions(-) diff --git a/backends/imgui_impl_opengl3.cpp b/backends/imgui_impl_opengl3.cpp index 2048603c4..4b9b2e007 100644 --- a/backends/imgui_impl_opengl3.cpp +++ b/backends/imgui_impl_opengl3.cpp @@ -14,6 +14,7 @@ // CHANGELOG // (minor and older changes stripped away, please see git history for details) +// 2021-06-25: OpenGL: Use OES_vertex_array extension on Emscripten + backup/restore current state. // 2021-06-21: OpenGL: Destroy individual vertex/fragment shader objects right after they are linked into the main shader. // 2021-05-24: OpenGL: Access GL_CLIP_ORIGIN when "GL_ARB_clip_control" extension is detected, inside of just OpenGL 4.5 version. // 2021-05-19: OpenGL: Replaced direct access to ImDrawCmd::TextureId with a call to ImDrawCmd::GetTexID(). (will become a requirement) @@ -94,6 +95,12 @@ // GL includes #if defined(IMGUI_IMPL_OPENGL_ES2) #include +#if defined(__EMSCRIPTEN__) +#ifndef GL_GLEXT_PROTOTYPES +#define GL_GLEXT_PROTOTYPES +#endif +#include +#endif #elif defined(IMGUI_IMPL_OPENGL_ES3) #if (defined(__APPLE__) && (TARGET_OS_IOS || TARGET_OS_TV)) #include // Use GL ES 3 @@ -132,6 +139,17 @@ using namespace gl; #endif #endif +// Vertex arrays are not supported on ES2/WebGL1 unless Emscripten which uses an extension +#ifndef IMGUI_IMPL_OPENGL_ES2 +#define IMGUI_IMPL_OPENGL_USE_VERTEX_ARRAY +#elif defined(__EMSCRIPTEN__) +#define IMGUI_IMPL_OPENGL_USE_VERTEX_ARRAY +#define glBindVertexArray glBindVertexArrayOES +#define glGenVertexArrays glGenVertexArraysOES +#define glDeleteVertexArrays glDeleteVertexArraysOES +#define GL_VERTEX_ARRAY_BINDING GL_VERTEX_ARRAY_BINDING_OES +#endif + // Desktop GL 3.2+ has glDrawElementsBaseVertex() which GL ES and WebGL don't have. #if !defined(IMGUI_IMPL_OPENGL_ES2) && !defined(IMGUI_IMPL_OPENGL_ES3) && defined(GL_VERSION_3_2) #define IMGUI_IMPL_OPENGL_MAY_HAVE_VTX_OFFSET @@ -323,7 +341,7 @@ static void ImGui_ImplOpenGL3_SetupRenderState(ImDrawData* draw_data, int fb_wid #endif (void)vertex_array_object; -#ifndef IMGUI_IMPL_OPENGL_ES2 +#ifdef IMGUI_IMPL_OPENGL_USE_VERTEX_ARRAY glBindVertexArray(vertex_array_object); #endif @@ -358,7 +376,7 @@ void ImGui_ImplOpenGL3_RenderDrawData(ImDrawData* draw_data) GLuint last_sampler; if (g_GlVersion >= 330) { glGetIntegerv(GL_SAMPLER_BINDING, (GLint*)&last_sampler); } else { last_sampler = 0; } #endif GLuint last_array_buffer; glGetIntegerv(GL_ARRAY_BUFFER_BINDING, (GLint*)&last_array_buffer); -#ifndef IMGUI_IMPL_OPENGL_ES2 +#ifdef IMGUI_IMPL_OPENGL_USE_VERTEX_ARRAY GLuint last_vertex_array_object; glGetIntegerv(GL_VERTEX_ARRAY_BINDING, (GLint*)&last_vertex_array_object); #endif #ifdef GL_POLYGON_MODE @@ -385,7 +403,7 @@ void ImGui_ImplOpenGL3_RenderDrawData(ImDrawData* draw_data) // Recreate the VAO every time (this is to easily allow multiple GL contexts to be rendered to. VAO are not shared among GL contexts) // The renderer would actually work without any VAO bound, but then our VertexAttrib calls would overwrite the default one currently bound. GLuint vertex_array_object = 0; -#ifndef IMGUI_IMPL_OPENGL_ES2 +#ifdef IMGUI_IMPL_OPENGL_USE_VERTEX_ARRAY glGenVertexArrays(1, &vertex_array_object); #endif ImGui_ImplOpenGL3_SetupRenderState(draw_data, fb_width, fb_height, vertex_array_object); @@ -443,7 +461,7 @@ void ImGui_ImplOpenGL3_RenderDrawData(ImDrawData* draw_data) } // Destroy the temporary VAO -#ifndef IMGUI_IMPL_OPENGL_ES2 +#ifdef IMGUI_IMPL_OPENGL_USE_VERTEX_ARRAY glDeleteVertexArrays(1, &vertex_array_object); #endif @@ -455,7 +473,7 @@ void ImGui_ImplOpenGL3_RenderDrawData(ImDrawData* draw_data) glBindSampler(0, last_sampler); #endif glActiveTexture(last_active_texture); -#ifndef IMGUI_IMPL_OPENGL_ES2 +#ifdef IMGUI_IMPL_OPENGL_USE_VERTEX_ARRAY glBindVertexArray(last_vertex_array_object); #endif glBindBuffer(GL_ARRAY_BUFFER, last_array_buffer); @@ -559,7 +577,7 @@ bool ImGui_ImplOpenGL3_CreateDeviceObjects() GLint last_texture, last_array_buffer; glGetIntegerv(GL_TEXTURE_BINDING_2D, &last_texture); glGetIntegerv(GL_ARRAY_BUFFER_BINDING, &last_array_buffer); -#ifndef IMGUI_IMPL_OPENGL_ES2 +#ifdef IMGUI_IMPL_OPENGL_USE_VERTEX_ARRAY GLint last_vertex_array; glGetIntegerv(GL_VERTEX_ARRAY_BINDING, &last_vertex_array); #endif @@ -732,7 +750,7 @@ bool ImGui_ImplOpenGL3_CreateDeviceObjects() // Restore modified GL state glBindTexture(GL_TEXTURE_2D, last_texture); glBindBuffer(GL_ARRAY_BUFFER, last_array_buffer); -#ifndef IMGUI_IMPL_OPENGL_ES2 +#ifdef IMGUI_IMPL_OPENGL_USE_VERTEX_ARRAY glBindVertexArray(last_vertex_array); #endif diff --git a/docs/CHANGELOG.txt b/docs/CHANGELOG.txt index 0cd04241f..3b18dc012 100644 --- a/docs/CHANGELOG.txt +++ b/docs/CHANGELOG.txt @@ -63,6 +63,7 @@ Other Changes: about building on 32-bit systems. (#4225) [@kingofthebongo2008] - Backends: OpenGL3: Handle GL_CLIP_ORIGIN on <4.5 contexts if "GL_ARB_clip_control" extension is detected. (#4170, #3998) - Backends: OpenGL3: Destroy vertex/fragment shader objects right after they are linked into main shader. (#4244) [@Crowbarous] +- Backends: OpenGL3: Use OES_vertex_array extension on Emscripten + backup/restore current state. (#4266, #4267) [@harry75369] - Backends: OSX: Added a fix for shortcuts using CTRL key instead of CMD key. (#4253) [@rokups] - Examples: OSX+OpenGL2: Fix event forwarding (fix key remaining stuck when using shortcuts with Cmd/Super key). Other OSX examples were not affected. (#4253, #1873) [@rokups]